セックスはスキンシップに始まり、スキンシップに終わる。Sex starts with caressing and touching and ends with caressing and touching.

子供とのスキンシップを大切にしないとね。 Skin contact is very important for kids.

Notes:1. This word is part of the 和製英語 （わせいえいご）family; words that sounds like English but.. aren't. As this word is particularly hard to directly translate, it's better seen with examples. Skinship is simply touching, rubbing, carressing, etc with those that are close to you. You can have skinship with children, pets, and of course, 恋人. I yanked the second example and translation straight from Jim Breen.

2. I learned the word in class, but got the above 例文 from Googling 「スキンシップ」, and a site dealing with.. vibrators came up! The following sentence reads バイブを使うときにも、このことは忘れずにいて下さい。 I thought that was kind of funny.. the whole website can be found here for all you perverts out there ;)

彼女に「３ヶ月浮気（うわき）してるよ」と言ったら、ビンタされた。When I told my girlfriend I've been cheating on her for three months, she slapped me across the face.

Notes:ビンタする is only used in a very particular context: when a woman slaps a man across the face (once or twice). For other means of slapping, you can use ひっぱたく, which is a slap to the face for both genders, and たたく, which is the more universal/flexible slap/pat.

一般的(いっぱんてきに)に日本人は集団行動しているので、ほとんどのアメリカ人には日本人の考え方が理解できない。Because Japanese typically act in a collective manner, it's difficult for Americans to understand the Japanese mind.

Notes:

集団行動 can also be used simply as a noun. For example, I pulled the example from my friend's journal, in which she wrote 集団行動が苦手, "I'm not very good with collective behavior. (which I find a bit ironic, being she is Japanese).